The science of Breaking Bad: Ozymandias

Breaking Bad | Season 5 | Episode 14 | “Ozymandias”

The lone and level sands stretch far away.

There are no winners in this week’s episode (with the possible exception of Uncle Jack and his crew) as all of Walt’s decisions and lies finally catch up with him, ripping everyone’s world apart. There is a little science to talk about, if you spotted it before everything kicked off.

So Jesse did end up captured and cooking for Uncle Jack, but not at all in the way I envisaged. It now seems unlikely that Walt would come back to Albuquerque packing a military arsenal just for him, and his money probably wouldn’t be worth much to him anymore without his family. What therefore is Walt’s plan? Presumably he would only come out of hiding to address a threat to Skyler/Junior/Holly/Marie, but what could anyone gain from going after them?

If we assume that Walt is planning on taking down Uncle Jack then his choice of weapon is a little unusual. The M-60 is too heavy to be used on foot, so he has to be planning on taking up a static position or firing from a vehicle. If he were storming Jack’s facility alone then lighter weapons, armour and explosives might be a better choice. Perhaps he’s going to take out a convoy from an ambush position?

Onto the science: Flask or beaker? I was asked this as we saw the flashback to Walt and Jesse’s first cook. It’s a flask – specifically, a 2000 ml Büchner flask (although Walt does not seem to be using it to filter anything). Beakers have straight sides and a spout.

Clearly the condensed liquid would cool more quickly in a freezer, but why is it important that the reaction is exothermic? Walt seems to be conflating a couple of reaction concepts here – equilibrium and rate.

In general, the rate of a chemical reaction will increase as temperature increases. This isn’t always true, but for most reactions the additional kinetic energy will encourage molecules to collide more (and hence react), and/or provide some of the activation energy (the initial energy input needed to get the reaction to start).

Equilibrium, on the other hand, describes the extent to which reactants will transform into reaction products. Say you have two molecules A and B, which will combine to give a third molecule C. If you start with 100 molecules of A and B and start the reaction then you might expect to get 100 molecules of C. However, in reality you might just as easily get 90 molecules of C and have 10 of A and B left over (or 60 C + 40 A/B, or 20 C + 80 A/B). Equilibrium describes this balance of reactants and products, and is dependent on temperature.

If Walt’s reaction is exothermic then it produces heat, which will actually inhibit the progress of the reaction. If the reaction can be artificially cooled then the final distribution of products (A + B and C) will favour C more than if the reaction happened at a higher temperature. It may not make the reaction happen any faster, though I don’t actually know how the rate of the methamphetamine cook depends on temperature.